While the authors suggested that people eat a low protein diet in middle age and switch to a high protein diet once they get older, it is not possible to say from the study whether this is what the older participants actually did, as their diets were only assessed once.

"Interestingly enough, blood triglycerides do not go up with eating fat—they go up if you eat a diet high in processed grains, starches, and sugar. Unfortunately for the proponents of high-carbohydrate diets, high blood triglycerides are a major risk factor for heart disease. In addition, low fat/high carb diets lower protective "good" cholesterol and raise insulin. These diets are implicated in the development of diabetes, which is a potent risk factor for developing heart disease."